Methods and steps for measuring current and voltage with a multimeter
A digital multimeter, also known as a multimeter, multimeter, multimeter or three-purpose meter, is a multi-purpose electronic measuring instrument that generally includes ammeter, voltmeter, ohmmeter and other functions. Compared with pointer multimeters, digital multimeters have the advantages of high precision, fast speed, large input impedance, digital display, accurate readings, strong anti-interference ability, and high degree of measurement automation and are widely used. However, if used improperly, it may cause malfunction. Let the editor of Electrician Home introduce to you one by one the methods and steps of using a multimeter to measure current and voltage.
1. Before using the multimeter, you should first perform a "mechanical zero adjustment", that is, when there is no electricity being measured, the multimeter pointer should point at the zero voltage or zero current position.
2. When using the multimeter, do not touch the metal part of the test lead with your hands. This can ensure accurate measurement on the one hand, and personal safety on the other hand.
3. When measuring a certain amount of electricity, you cannot change gears while measuring, especially when measuring high voltage or large current, you should pay more attention. Otherwise, the multimeter will be damaged. If you need to change gears, you should disconnect the test leads first, and then measure after changing gears.
Steps to measure current and voltage using a multimeter
1. Select the measurement range. The DC voltage range of the multimeter is marked with "V" and has five ranges: 2.5 volts, 10 volts, 50 volts, 250 volts and 500 volts. Select the range according to the power supply voltage in the circuit. Since the power supply voltage in the circuit is only 3 volts, the 10 volt range is selected. If you don't know the voltage, you should first measure with the highest voltage level and gradually switch to the lower voltage level.
2. Measurement methods. The multimeter should be connected in parallel with the circuit under test. The red pen should be connected to the connection between the circuit under test and the positive pole of the power supply, and the black pen should be connected to the connection between the circuit under test and the negative pole of the power supply.
3. Correct reading. Observe the dial carefully. The DC voltage scale line is the second scale line. When using the 10V scale, you can directly read the measured voltage value by using the third row of numbers under the scale line. When taking a reading, your eyes should be facing the pointer.
